Search for dissertations about: "mean transit time"

Showing result 1 - 5 of 12 swedish dissertations containing the words mean transit time.

  1. 1. Analysis of Angiographies in Human Healthy Eyes and in Open-angle Glaucoma Retinal Mean Transit Time and Optic Nerve Head Circulation

    University dissertation from Uppsala : Acta Universitatis Upsaliensis

    Author : Gunilla Bjärnhall; Uppsala universitet.; [2008]
    Keywords : MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; MEDICINE Physiology and pharmacology Ophtalmology; MEDICIN Fysiologi och farmakologi Oftalmologi;

    Abstract : Purpose of the studies was to develop a more robust technique to determine retinal mean transit time in healthy and in glaucoma eyes and to evaluate the circulation of the optic nerve head in glaucoma patients.The retinal mean transit time impulse-response method was evaluated in human healthy eyes and normal values and reproducibility were tested. READ MORE

  2. 2. Studies on Retinal Circulation in Experimental Animals, Healthy Human Eyes and Eyes with Diabetic Retinopathy

    University dissertation from Uppsala : Acta Universitatis Upsaliensis

    Author : Lidija Tomić; Uppsala universitet.; [2008]
    Keywords : MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Retinal Circulation; Labelled Microsphere Technique; Monkeys; Blue Field Simulation; Macular Leukocyte Velocity; Fluorescein Angiogram; Mean Transit Time; Impulse-Response Technique; Arterio-Venous Passage Time; Vessel Diameter; Oxygen; Carbin Dioxide; Diabetes Retinopathy; MEDICINE Physiology and pharmacology Ophtalmology; MEDICIN Fysiologi och farmakologi Oftalmologi;

    Abstract : The retina is a highly metabolically active tissue with large demands on the supply of nutrients. Disorders affecting the retina often include some vasculopathy with an impact on retinal circulation. READ MORE

  3. 3. Optimisation and Validation of Dynamic Susceptibility Contrast MRI Perfusion Measurements

    University dissertation from Lund University (Media-Tryck)

    Author : Linda Knutsson; Lund University.; Lunds universitet.; Lund University.; Lunds universitet.; [2006]
    Keywords : MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Nukleärmedicin; radiobiologi; Nuclear medicine; radiobiology; radiologi; tomografi; medicinsk instrumentering; tomography; medical instrumentation; Clinical physics; cerebral blood volume; mean transit time; cerebral blood flow; perfusion; dynamic susceptibility contrast MRI arterial input function; Klinisk fysiologi; radiology;

    Abstract : The studies presented in this thesis concern the optimisation and evaluation of the dynamic susceptibility contrast magnetic resonance imaging (DSC-MRI) technique for the assessment of perfusion-related parameters of the brain, such as cerebral blood flow (CBF), cerebral blood volume (CBV) and mean transit time (MTT). Several methodological factors influence these measurements, for example, contrast-agent administration, arterial input function (AIF) registration, choice of deconvolution algorithm and the choice of pulse-sequence parameters. READ MORE

  4. 4. MRI Perfusion Measurements using Magnetic Susceptibility Effects: : Calibration Approaches and Contrast Agent Quantification

    University dissertation from Naturvetenskapliga fakulteten, Lunds universitet

    Author : Emelie Lind; Lund University.; Lunds universitet.; Lund University.; Lunds universitet.; [2019-02]
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; contrast agent; cerebral blood flow; cerebral blood volume; mean transit time; perfusion; dynamic susceptibility contrast MRI; magnetic susceptibility;

    Abstract : Exchange of oxygen and nutrients between blood and tissue occurs at the capillary level of the blood system. The blood volume flow rate in the capillaries is often referred to as perfusion, and knowledge about perfusion provides important information about the function and viability of the tissue, for example, in patients with ischaemic stroke, cancer, and neurodegenerative diseases. READ MORE

  5. 5. Frequency Transfer Techniques and Applications in Fiber Optic Communication Systems

    University dissertation from Naturvetenskapliga fakulteten, Lunds universitet

    Author : Sven-Christian Ebenhag; RISE.; [2013]
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; synchronous digital hierarchy SDH ; UTC; synchronization; Time transfer; optical fiber; optical fiber network; GPS carrier phase; global positioning system GPS ; synchronous optical networking SONET ;

    Abstract : Modern society is dependent on communications and the developments of these increases constantly through a seemingly endless demand for communication services and thereby synchronization and time. This is confirmed by a vast range of research on communications, irrespective of technology and protocol. READ MORE